ORIGINAL: FOOPED
The bolt pattern is correct. I marked it out on a large board and mounted the engine .Then I bolted a flat board on the prop adabtor and a pin and turned the prop with pin on it full rotation and this gives dead center for prop swing. The 49 should be divided like this. from center down bottom of engine mounting bolt is 30mm and up to top of engine mounting bolt is 19mm . Hope this helps you. Fooped
Thank you for the input. But I don't understand how it proves 49 mm is correct. The standoffs that comes with the engine is 50 mm long and the diameter of the bottom is approximately 14 mm, top end is about 11 mm, the hole is off centered varying from almost right on up to 1 mm. If you are 1 mm off, that takes 0.5 mm from each end. The tilt would be arctangent (0.01) or 0.00017 degrees. The board will dent slightly but you won't notice.
However, if you make a metal bracket that mates directly to the engine mount, 1 mm will be a big difference.